SIP panels with integral ventilation…anyone used them?
A Mn based SIP maker (Enercept) told me they can make a SIP panel with integral ventilation under the outer layer of OSB. I was hoping for such a thing to help reduce the issue with rot at the peak of a roof SIP panel. Yes, interior air barriers are crucial as well, but it would seem that ventilation between the foam core and the outer layer of OSB would be helpful as well. One way they can do it is by grooving the EPS foam before applying the OSB. I think they have another way (firing strips). Has anyone used such a product and if so, what pros/cons did you encounter? Seems like it would make sense for a SIP wall panel too. Thanks Much- Bob
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I do not see any use of this for walls. Even with channels cut into the foam a large percentage of the OSB will be backed directly to the foam. While it will allow limited drying a ventilated rainscreen would be much better. This would be further limited by wall openings (doors and windows). For a hot roof it would be better than nothing. I wonder how they provide ventilation access at the soffit and peak (also between panels on long roof runs)?
I know hunter panel makes them with sleepers and Iso foam.
I considered them but they were pricey and they charged minimums and shipping
Robert,
Hunter panels are nailbase panels, with OSB on one side only, intended for roofs. They have integral ventilation:
http://www.hpanels.com/2009/pages/pdfs/Lit_Prod_Color/Cool-Vent.pdf
When it comes to walls, I agree with Nathan -- you want a traditional rainscreen with vertical furring strips or a three-dimensional drainage mat.
I'm no engineer buuuuttt...
I would think what you're suggesting Martin would decrease the strength of the panel, no? Less contact, less strength. would seem like a panel of a product like cor-a-vent, fulley adhered on both sides would be ideal, right? Can't imagine what that would cost....
Thanks so much for the input and good point on the wall SIP. I still like the idea of venting under that roof SIP osb. Any interior moisture that gets up there (think Juneau roof rot issues) will stand a better chance of drying. IE much more likely the drying rate will be > the wetting rate. And added cost still likely to be < labor/material cost of adding strapping and another decking layer before installing the the continuous Ice/water that is my standard under a metal (or any other 'lifetime') roof.